From 1 April 2012 E.C. Regulation 883/2004 will be extended to cover Switzerland. HMRC will now treat Switzerland as being another E.U. Member State for Social Security purposes. This means that if an individual goes to live or work in Switzerland from 1 April 2012 then the new rules will apply to them and their employer. The impact of this depends upon the circumstances of the employment but it may result in U.K. nationals continuing to pay U.K. National Insurance contributions during their time in Switzerland or in Swiss employers having to contribute to the U.K. system if they have employees living and working in the U.K. and paying U.K. contributions.
The new rules also apply to self-employed people moving between the U.K. and Switzerland.
There are special transitional rules that apply to the new regime. The previous rules were, in fact, very similar but if the new rules would result in any change to an individual's circumstances then they may be able to continue with existing arrangements until there is a change in their circumstances.